# Mathematical Basics for GAMG

 Register Blogs Members List Search Today's Posts Mark Forums Read

 April 14, 2008, 10:53 Hi, I'm searching for the m #1 Member   Joern Bader Join Date: Mar 2009 Posts: 33 Rep Power: 8 Hi, I'm searching for the mathematical basics of the GAMG Solver. In my literature i only find GMG and AMG. I want to know how the GAMG works and whats the difference to GMG and AMG. Joern

 April 14, 2008, 14:11 GAMG is geometric/algebraic MG #2 Super Moderator   Mattijs Janssens Join Date: Mar 2009 Posts: 1,416 Rep Power: 16 GAMG is geometric/algebraic MG. Instead of the agglomeration being calculated from the matrix coefficients (and thus differ every 'solve') this one can use an agglomeration based on geometry (which is usually constant and can be cached). See the 1.4 release notes. http://www.opencfd.co.uk/openfoam/doc/ReleaseNotes-1.4

 April 15, 2008, 04:15 Hi Mattijs, how can I adjus #3 Senior Member   Fabian Braennstroem Join Date: Mar 2009 Posts: 407 Rep Power: 10 Hi Mattijs, how can I adjust the agglomaration? Is setting cacheAgglomeration to true enough for the geometric and setting it to false ennough for the algebraic version? Thanks! Fabian

 April 15, 2008, 15:53 enter an invalid name for the #4 Super Moderator   Mattijs Janssens Join Date: Mar 2009 Posts: 1,416 Rep Power: 16 enter an invalid name for the agglomeration and you'll see the possible agglomeration methods. You can make your own one. Look e.g. at pairGAMGAgglomeration.H. Cache the agglomeration if you don't mind the extra storage and it does not change.

 April 17, 2008, 11:01 Ah, I see, the choices are alg #5 Senior Member   Fabian Braennstroem Join Date: Mar 2009 Posts: 407 Rep Power: 10 Ah, I see, the choices are algebraicPair and faceAreaPair; I assume that one would mostly use the faceAreaPair as long as there is no mesh motion and no automatic mesh adaption!? Thanks! Fabian

 December 11, 2008, 09:45 Hi, I wonder, if there is a #6 Senior Member   Fabian Braennstroem Join Date: Mar 2009 Posts: 407 Rep Power: 10 Hi, I wonder, if there is an option to write out the agglomerated coarse mesh for every level? Thanks in advance! Fabian

 December 18, 2008, 03:17 Hi, me again... do you hav #7 Senior Member   Fabian Braennstroem Join Date: Mar 2009 Posts: 407 Rep Power: 10 Hi, me again... do you have a hint, if the use of an agglomerated coarse mesh is the good approach to get a coarse surface and volume mesh!? I would like to use a real coarse mesh for thermal calculations of a room divided in a couple of regions. Fabian

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post tutlhino OpenFOAM Running, Solving & CFD 5 January 26, 2013 17:01 bastil OpenFOAM Running, Solving & CFD 2 March 2, 2009 04:21 sivakumar OpenFOAM Running, Solving & CFD 1 October 20, 2008 06:40 piotr OpenFOAM Running, Solving & CFD 0 April 23, 2008 07:09 msrinath80 OpenFOAM Running, Solving & CFD 2 May 31, 2007 15:28

All times are GMT -4. The time now is 17:42.